ENVIRONMENTAL POLICY
decision apparently based on incontrovertible objective criteria). Conversely,
whilst an EIA can also be undermined by unreliable or incomplete data,
it is the qualitative methodology and the openness of its conclusions that
may reduce its authority. The terms of reference for an individual EIA may
also produce biased outcomes, particularly where, as in Australia, it is the
responsibility of the private developer, rather than an independent body,
tocarry out the EIA. Overall, although promulgated as objective tools of
rational analysis, each of the three techniques contains fundamental con-
ceptual and technical weaknesses that render it vulnerable to charges of
bias, unreliability and imprecision.
Secondly, these methodological weaknesses contribute to the uneasy inter-
face between science and politics that characterises many environmental
problems. Even risk assessment practitioners are unable to reach a consen-
sus about what constitutes an ‘acceptable’ level of risk; instead, they hand
the problem over to the policymaker, who may be guided by public opinion
when deciding how to manage a particular risk. Yet public perceptions of
risk are socially constructed and depend on a wide range of factors, includ-
ing the position of an individual in society, and whether the possible con-
sequences of an action are delayed or immediate (Adams 1995 ;Liberatore
1995 ). Thus ‘NIMBYism’ is often fuelled by a gross exaggeration of the real
risk to health from a proposed development such as an incinerator or land-
fill site, but fierce public opposition may persuade the politician to override
ascientific risk assessment that judges the proposal to be safe. By contrast,
people are more tolerant of risks they bear voluntarily, such as smoking, or
where, as with car ownership, halting an activity might have high personal
costs.
From an ecocentric standpoint, CBA is morally unacceptable because it
places a monetary value on wildlife or wilderness. It might be countered
that the practice of valuing human life is common in healthcare provision,
where the allocation of scarce resources involves similar difficult trade-offs
between priorities, so why not extend it to nature? A more persuasive objec-
tion to CBA is that, while monetary valuation may be meaningful for some
small-scale incidences of localised air or noise pollution, many important
environmental goods are simply not commensurable in this way (Jacobs
1991 ). How can a value be placed on an endangered species, irreplaceable
rainforest or an undamaged ozone layer? A CBA may provide useful informa-
tion for policymakers but, like risk assessment, its claims to objectivity often
leave them no better equipped to arbitrate between different interests. Ulti-
mately, this apparent weakness may be no bad thing, for political decisions
cannot – and should not – be reduced to a mathematical exercise: ‘such
choices must be a matter of judgement, not computation’ (ibid.: 219). In this
respect, whereas CBA reduces the flexibility for political judgement by pro-
viding a cut-and-dried calculation about whether the benefits of a proposal
exceed the costs (Pearce 1998 ), an advantage of EIA is that underpinning
its longer checklist of potential impacts and lack of a definitive conclusion